The present invention relates to a system for measuring and/or monitoring the intraocular pressure (IOP). The present invention relates in particular to a system comprising a device that can be placed on or in the eye of a user to monitor intraocular pressure over an extended period of time, wherein the system further comprises inertial and optionally environmental sensors in order to allow correlating the thus collected inertial and optionally environmental information with the intraocular pressure measurements.
Glaucoma is a widespread disease characterized by an elevated intraocular pressure (IOP). This elevated IOP produces a gradual loss of peripheral vision. There is therefore a need to have a detailed knowledge of IOP in glaucoma patients in order to provide reliable diagnostics or for setting up new therapies.
There are several types of devices that are commonly used for measuring IOP on patients. Some devices are configured for single measurements and are usually bulky fixed equipments. A pressure sensor is applied on the patient's eye with a determined pressure for a short period of time.
Other equipments allow IOP measurement over extended periods of time, for example some hours, days or more. These devices often comprise a miniaturized pressure sensor, for example in the form of a MEMS, that is worn by the patient during the entire measuring time period. The pressure sensor is for example integrated into or attached to a contact lens worn by the patient, or mounted on a support configured to be directly implanted into the eyeball. The pressure sensor continuously measures the IOP as long as it is in contact with the eye, and the measured pressure values are transmitted to and for example stored by a receiver over a wired or a wireless communication link.
An advantage of such pressure measuring devices or systems is that they allow measuring the IOP of a patient over an extended period of time, thereby allowing monitoring the evolution of the IOP during the day, allowing for example measuring possible pressure differences depending on whether the patient is awake or asleep, tired or not, etc.
WO 2011/035262 and US 2003/0078487 for example describe implantable intraocular pressure monitoring devices, and WO 2011/083105 describes an intraocular pressure monitoring device united to a contact lens, that all communicate wirelessly with a remote device. These devices may for example be used to measure intraocular pressure over extended time periods.
However, it might be sometimes difficult to analyze some of the measured IOP variations that can be due to external factors, for example the patient's physical activity and/or environment at the time of IOP measurement.